A papermaking mold used to manufacture pulp molded articles usually has a net on the inner surface of its papermaking part. The net is generally fixed to the mold by welding or with metal wire, etc. Otherwise, the net would move out of a prescribed position during papermaking by the pressure or the flow of a pulp slurry injected, etc., which results in a failure to obtain a molded article of a desired shape or results in a non-uniform thickness of the resulting molded article.
As a mold with a net is used repeatedly for producing molded articles, pulp fiber is adhered and accumulated on the net to cause unevenness in thickness of molded articles or impair the appearance of molded articles. Thus, it is necessary for the net to be removed and cleaned. However, where the net is fixed by welding, it is not easy to remove the net. Where it is fixed with wire, etc., removal is possible but laborious.
In a conventional papermaking mold, a mold clamping force is applied to the peripheral part of the mold where the papermaking net is disposed so that the force is directly exerted on the net. As a result, the net is deformed on clamping and gradually damaged from repetition of papermaking and eventually needs an exchange. Where, in particular, a wet preform after papermaking and dewatering is transferred from the papermaking mold to a drying mold by purging with compressed air and suction, the frequency of mold opening and closure increases, and the part of the net which covers the peripheral part of the mold which extends outward from the papermaking part suffers considerable damage. This problem occurs in conjunction with the above-mentioned difficulty of net exchange where the net is fixed to the mold by welding or with wire, etc. Therefore a papermaking mold of which the net hardly suffers damage from repeated use of the mold has been desired.
Accordingly, an object of the present invention is to provide a papermaking mold the net of which can be attached and detached with improved ease.
Another object of the present invention is to provide a papermaking mold which reduces damage to the net thereof when used repeatedly.